CSE 221: Homework 3

Fall 2005

Due: Section A (Marzullo): Monday, November 28, 2005 at the start of class (5pm)
Due: Section B (Voelker): Tuesday, November 29, 2005 at the start of class (9:30am)

In 1999, Wang et al. proposed a disk drive architecture
supporting a service called "eager write". Rather than update a block
in place, as with normal disks, an eager writing disk simply writes to
the next free block near the disk head (the disk internally keeps
track of this mapping by maintaining a table mapping "logical" disk
blocks to physical disk blocks). Argue whether using such a disk
would improve the performance of a Log-Structured File System, hurt
its performance, or make little difference.

Many of the papers we have read can be placed into one
of two categories: papers that attempt to virtualize a resource to
provide transparency to the underlying implementation, and papers that
attempt to expose a resource to allow applications to improve their
performance. For the following systems, describe which resource is
virtualized or exposed and what they hoped to accomplish by doing
this: